The present invention relates to a shoe sole, in particular for athletic shoes, that has an outsole and a cushioning midsole, and parts of the midsole comprise recesses or cells that extend essentially perpendicular to the plane of the sole.
Such a shoe sole is known from German Utility Model 89 01 235 and its corresponding U.S. Pat. No. 5,084,987. In this known shoe sole, honeycomb cells or recesses, that extend perpendicular to the plane of the sole, are placed only in the central area under the heel bone or heel bone and ball of the foot to achieve there, on the one hand, good damping, but on the other hand, also to achieve high resiliency, and the entire midsole consists of foamed plastic. Similarly, U.S. Pat. No. 4,245,406 shows an athletic shoe in which the entire midsole is formed of a foamed plastic material, and a honeycomb-like structure of hollow regions and ridges is created in the region extending rearwardly of the metatarsal area.
Furthermore, from U.S. Pat. No. 4,449,307 and U.K. Patent 510,426, outsoles are known which are formed of a compact, i.e., unfoamed, plastic or rubber material in which arrangements of ridges and recesses are formed at the upper surface thereof to increase the flexibility of the outsole. In shoes with these soles, the insole or footbed sits directly on the outsole without any cushioning midsole being provided. Likewise, in German Utility Model No. 87 14 058, a sole is formed of a compact, i.e., unfoamed, gum rubber material in which arrangements of lamellae-like ridges form air chambers that are open toward the tread surface of the sole but are closed by the tread layer that is applied to the bottom of the sole. The top of the sole is closed and in one embodiment, a footbed of a foamed material is applied thereon which has channels which enable the air chambers to "breath" through the footbed.